\name{Startup}
\title{Initialization at Start of an R Session}
\usage{
.First <- function() { \dots\dots }

.Rprofile <startup file>
}
\alias{Startup}
\alias{Rprofile}
\alias{.Rprofile}
\alias{.First}
\description{
  In \R, the startup mechanism is as follows. If a file
  \file{.Renviron}, or failing that \file{\eqn{\sim}{~}/.Renviron},
  exists, it is
  sourced, usually to set environmental variables. This is suppressed
  by the flag \code{--no-environ}. Then \R searches for
  the site-wide startup profile unless the command line option
  \code{--no-site-file} was given.  The name of this file is taken
  from the value of the \file{R\_PROFILE} environment variable.  If that
  variable is unset, the default is \file{\$R\_HOME/etc/Rprofile}.

  Then, unless \code{--no-init-file} was given, \R searches for a file
  called \file{.Rprofile} in the current directory or in the user's
  home directory (in that order) and sources it.

  It also loads a saved image from \file{.RData} if there is one
  (unless \code{--no-restore} was specified).

  Finally, if a function \code{.First} exists, it is executed as
  \code{.First()}.

  The functions \code{.First} and \code{\link{.Last}} can be defined
  in the appropriate startup profiles or reside in \file{.RData}.

  The command-line flag \code{--vanilla} implies \code{--no-init-file},
  \code{--no-restore} and \code{--no-environ}.
}
\seealso{
  \code{\link{.Last}} for final actions before termination.
}
\keyword{environment}
